It probably is if you don't know anything about them and what to look for when buying a used SC. Good deals are out there but some are priced low for a reason.
What kind of Vortech is it? There are lots of models.
Post a picture of the tag on the supercharger unit and let's go from there. I can get you service records and build info from Vortech. Does it come with all of the supporting brackets and hardware? Once we get a look at the tag I can give you a lot more info on everything.
if you dont know how to check it for condition, either take it to someone that does know, or stay far away from it. $600 can be a heck of a deal, or like some have said, you are buying a boat anchor. and you need do more than just spin it to see if it works.
Post a picture of the tag on the supercharger unit and let's go from there. I can get you service records and build info from Vortech. Does it come with all of the supporting brackets and hardware? Once we get a look at the tag I can give you a lot more info on everything.